SAAB WIS ONLINE

Input shaft speed sensor

Input shaft speed sensor

The input speed sensor is mounted in the gearcase. It provides the control module with information on the speed of the gearbox input shaft on pin 9. The sensor is grounded via pin 30.

The sensor is of electromagnetic (inductive) type and measures the input speed after the torque converter (turbine rpm) by means of pulses generated by a 12-toothed wheel (C1 clutch drum). The control module uses the frequency of the pulses to calculate the input speed. Sensor voltage increases with increasing engine speed. At idling speed the voltage is approx. 1.2-1.4 V AC and at 2500 rpm 2.2 V AC.

Resistance between pins is 300-600 Ohm.

The control module uses the input speed and the vehicle speed to calculate shifting times and the position of the accelerator pedal. The two speeds affect the engine torque limitation, which results in smoother shifting.


Diagnostics

If input speed is absent, diagnostic trouble code P0717 will be generated and the TCM will go into Limp-Home mode.